CN101235055A - A kind of method of manufacturing sodium lignosulfonate - Google Patents

Abstract

The invention relates to a method for manufacturing sodium lignosulfonate, which comprises the following steps: dissolving treatment: adding lignin to the black liquor to make the solution concentration to a solid content of 30-45%; oxidation: dissolving the black liquor After heating to 50-70°C, add oxidant and catalyst, react for 50-70 minutes; sulfonation: add sulfonating agent to the oxidized solution, heat to 125-145°C, sulfonate for 90-180 minutes, the product is brown Liquid; also includes the step of hydroxylation: adding 2-5% by weight of the solution after oxidation treatment, with a concentration of 20-37% formaldehyde, and reacting at 70-80°C for 45-75 minutes. It also includes the step of spray drying: drying the sulfonated liquid through hot air at 240-260°C to obtain a powdery solid product. The invention uses the black liquor as the lignin solution, which not only saves caustic soda but also directly utilizes part of the black liquor, thereby saving costs. Dissolve directly to the sulfonation concentration, no need to concentrate before sulfonation, saving a lot of steam. The waste acid-analyzed lignin is converted into products required by the market, secondary pollution is eliminated, and it is suitable for popularization and application.

Description

A kind of method of manufacturing sodium lignosulfonate

(1) Technical field

The invention relates to the technical field of papermaking sewage treatment, in particular to a method for manufacturing sodium lignosulfonate.

(2) Background technology

Some paper-making enterprises use the method of acid analysis of lignin to process black liquor, most of which are stored as waste, occupying a large area of land and causing certain secondary pollution. Some manufacturers use it to make sodium lignosulfonate, but it must be redissolved with water and caustic soda. Some manufacturers sulfonate and modify the dark night, and then spray dry to manufacture sodium lignosulfonate. Concentration requires a lot of heat, and the product contains more impurities, which affects the quality. For example, the China Intellectual Property Office published a patent for invention on December 7, 2005, the patent application number is 200410044834.9, and the publication number is CN1704372. The process steps are as follows: use a concentrator to concentrate the pulping dilute black liquor to a thick black liquor with a solid content of 30-60%, then pump the thick black liquor into the reactor, add an acid regulator to adjust the pH value of the reaction system to 10.5-13.5, then add a catalyst with a mass fraction of 0.05-2.5% and a sulfonating agent of 1.5-20.0%, react at a reaction temperature of 80-120°C for 1-6 hours, add a calculated amount of additives, and react 0.5-3.0 After h, the product is cooled and discharged. The product is a tan liquid. After spray drying, the solid powder is obtained. The performance index of the product meets the performance index of the first-class product performance index of retarding water reducer in the GB8076-1997 standard, and the whole product of the present invention There is no discharge of "three wastes" in the production process, and the problem of black liquor pollution in pulp and paper mills is solved. Therefore, this preparation process is a clean and environmentally friendly process; but the present invention has the following problems: 1. The dark night concentration equipment requires a lot of investment, On a scale of 10,000 tons, the enrichment device is 5-6 million yuan, and the cost is relatively high. 2. To produce one ton of powdered sodium lignosulfonate in the production process, more than 5 tons of water needs to be evaporated in the concentration stage alone, which requires a lot of steam (about 30 yuan is needed to evaporate a ton of water for multi-effect evaporation). 3. The content of impurities is high, and sugar solution needs to be added to adjust the performance, and inorganic acid or organic acid needs to be added to adjust the pH, and the process steps are relatively complicated.

(3) Contents of the invention

In order to solve the problems of complex process, high cost and easy secondary pollution in the prior art, the present invention provides a method for manufacturing sodium lignosulfonate with simple process, low cost and avoiding secondary pollution.

The present invention is achieved through the following measures: a method for manufacturing sodium lignosulfonate, characterized in that: comprises the following steps:

1. Dissolving treatment: adding lignin to the black liquor to make the solution concentration to a solid content of 30-45%;

2. Oxidation: heat the dissolved black liquor to 50-70°C, add oxidant and catalyst, and react for 50-70 minutes;

3. Sulfonation: Add sulfonating agent to the solution after oxidation treatment, heat to 125-145°C, sulfonate for 90-180 minutes, the product is brown liquid;

After the step 2, the present invention also includes a step of hydroxylation: adding 2-5% by weight of the oxidized solution with a concentration of 20-37% formaldehyde, and reacting at 70-80° C. for 45-75 minutes.

The present invention also includes a step of spray drying after step 3: drying the sulfonated liquid through hot air at 240-260° C. into a powdery solid product.

The sulfonating agent of the present invention is sodium hydroxysulfate and sodium sulfite, and the addition amount is 2-30% by weight.

The catalyst described in the invention is ferrous sulfate, manganese dioxide or ferric chloride, and the addition amount is 1-5% by weight.

The oxidizing agent in the present invention is hydrogen peroxide with a concentration of 30-50%, and the addition amount is 1-10% by weight.

The lignin in the present invention is lignin analyzed by liquid acid, hot flue gas, lignin analyzed by sulfuric acid dioxide or lignin treated by drying.

The solid content of the solution concentration after dissolution described in the present invention is 38%.

Beneficial effects of the present invention:

1. Using black liquor as lignin solution saves caustic soda and directly uses part of black liquor, saving costs.

2. Dissolve directly to the sulfonation concentration, no need to concentrate before sulfonation, saving a lot of steam.

3. Using this process to produce sodium lignosulfonate products, the process is simple, the process is short, and the investment is low.

4. Transforming waste acid-analyzed lignin into market-demanding products eliminates secondary pollution and has economic and social benefits.

5. Easy to operate, low in cost, convenient and practical, and suitable for popularization and application.

(4) Description of drawings

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 1 is a schematic diagram of the process flow of the present invention.

In the figure 1. Dissolving tank, 2. Sulfonation reaction tank, 3. Spray drying tower.

(5) Specific implementation methods

The invention comprises the following steps: 1. Dissolving treatment: adding lignin to the black liquor to make the solution concentration to a solid content of 30-45%; 2. Oxidation: heating the black liquor after dissolving treatment to 50-70°C and then adding an oxidizing agent and catalyst, react for 50-70 minutes; 3. Sulfonation: Add sulfonating agent to the oxidation-treated solution and heat to 125-145°C, sulfonate for 90-180 minutes, the product is brown liquid; after step 2, there is also a step Hydroxylation: Add wt2-5% formaldehyde with a concentration of 20-37% to the solution after oxidation treatment, and react at 70-80°C for 45-75 minutes; after step 3, there is also a step of spray drying: after sulfonation The liquid is dried by hot air at 240-260°C to a powdery solid product. The sulfonating agent is sodium hydroxysulfate or sodium sulfite, and the addition amount is 2-30% by weight. The catalyst is ferrous sulfate, ferric chloride or manganese dioxide, and the addition amount is 2-30% by weight. The oxidizing agent is hydrogen peroxide with a concentration of 30-50%, and the addition amount is 1-10%. The lignin is lignin analyzed by liquid acid, hot flue gas, lignin analyzed by sulfuric acid dioxide or lignin treated by airing. The solid content of the solution concentration after the dissolution is 38%.

Example 1.

A method for manufacturing sodium lignosulfonate, adopting steps successively:

1. Dissolution treatment: Add 10 cubic meters of black liquor to dissolving tank 1 with a pH of 13, an alkali content of 32 g/L, and 7.6 degrees Baume, and add 3,200 kg of lignin under stirring, and mix and stir for 2 hours until it contains solids. The amount is 30%.

2. Oxidation: Heat indirectly to 65 degrees with steam, add 310 kg of 30% hydrogen peroxide and 30 kg of ferrous sulfate heptahydrate with a content greater than 85%, and stir for 60 minutes.

3. Hydroxylation: add 350 kilograms of 37% formaldehyde solution, raise the temperature to 75 degrees, stir and react for 50 minutes, then pump it into the sulfonation reaction tank 2.

4. Sulfonation: Open the feeding port of the airtight sulfonation reaction tank 2, add 660 kg of sodium sulfite with a purity of 96% to the solution that has been added to the solution that has been processed by the dissolution tank 1, and indirectly heat up to 140 ° C under stirring to maintain the temperature. Sulphonate for 150 minutes (the sulfonated solution can be used as a liquid product).

5. Push into the spray drying tower 3 with a pump and dry in hot air at 240-260° C. to a powdery solid product to obtain 4800 kg of product.

Table 1 The product prepared by the present invention compares with other similar products on the fluidity/mm of cement slurry: the water-cement ratio is 0.4

Dosage calcium lignin sulfonate Sodium lignin sulfonate (this example) 0.2% 190192 0.3% 202206 0.4% 218222

serial number Test items Performance test result Individual judgment First grade Qualified product 1 Water reduction rate (%) ＞＝8 ＞＝5 12 First grade 2 Bleeding rate (%) ＜＝100 ＜＝100 3 Gas content (%) ＜5.5 ＜5.5 2.8 First grade 4 Coagulation time (min) initial setting ＞+90 ＞+90 4:56 First grade final setting 6:08 5 Compressive Strength Ratio (%) 3d ＞＝100 ＞＝100 116 First grade 7d ＞＝110 ＞＝110 119 First grade 28d ＞＝110 ＞＝105 112 First grade 6 Shrinkage Ratio (%) 28d ＜＝135 ＜＝135 109 First grade 7 Effect on steel corrosion It should be stated whether there is any corrosion hazard to the steel bar No rust hazard qualified

              Table 2 Part of the performance indicators of the products produced by the present invention

Its quality indicators are as follows: sodium lignosulfonate content 45-50%, reducing content < 8%, water insoluble content < 2.5%, PH 8-11 water content < 8%, mortar water reducing rate 8-12%.

Example 2.

A method for manufacturing sodium lignosulfonate, adopting the following steps successively

1. Dissolution treatment: Add 20 cubic meters of black liquor with a pH of 13, an alkali content of 31g/l, and a degree of Baume of 7.56 into dissolving tank 1, and add 9,200 kg of lignin that has been air-dried under stirring until the solid content is reached. was 38%.

2. Oxidation: Heat indirectly to 70 degrees with steam, add 850 kg of 30% hydrogen peroxide and 20 kg of manganese dioxide, and stir for 70 minutes.

3. Sulfonation: Open the feeding port of the airtight sulfonation reaction tank 2, add 1300 kilograms of concentration to 60% α-hydroxyethyl sodium sulfate in the solution that has been added to the solution that has been processed by the dissolution tank 1, and indirectly heat up to 135 under stirring. ℃, maintain the temperature for sulfonation for 90 minutes, and obtain 32000 kg of sulfonated solution as a liquid product.

Example 3.

A method for manufacturing sodium lignosulfonate, adopting the following steps successively:

1. Dissolution treatment: 20 cubic meters of black liquor with a pH of 13, an alkali content of 32.5g/l, and 7.63 Baume degrees are added to the dissolution tank 1, and 13,000 kg of liquid acid-analyzed lignin is added under stirring until the solid content is 45%.

2. Oxidation: Heat indirectly with steam to 50 degrees, add 1100 kg of 30% hydrogen peroxide and 60 kg of 55% ferric chloride, and stir for 50 minutes.

3. Sulfonation: Open the feeding port of the airtight sulfonation reaction tank 2, add 2000 kg of 45% α-hydroxymethyl sodium sulfate to the solution that has been processed by the dissolution tank, and indirectly heat up to 135 ° C under stirring , maintain the temperature and sulfonate for 150 minutes. The sulfonated solution can be used as a liquid product.

4. Push into spray drying tower 3 with a pump and dry in hot air at 240-260° C. to be a powdery solid product to obtain 16,000 kilograms of product.

Claims (8)

1. a method for manufacturing sodium lignosulfonate, is characterized in that: comprise the following steps: 1) Dissolving treatment: adding lignin to the black liquor to make the solution concentration to a solid content of wt30-45%; 2) Oxidation: heating the dissolved black liquor to 50-70°C, adding an oxidizing agent and a catalyst, and reacting for 50-70 minutes; 3) Sulfonation: Add sulfonating agent to the oxidized solution, heat to 125-145°C, and sulfonate for 90-180 minutes; 2. the method for manufacturing sodium lignosulfonate according to claim 1, it is characterized in that: after step 2), also comprise step hydroxylation: add wt2-5% in the solution of post-oxidation treatment, concentration is 20- 37% formaldehyde, react at 70-80°C for 45-75 minutes. 3. The method for manufacturing sodium lignosulfonate according to claim 2, characterized in that: after step 3), the step of spray drying is included: the liquid after sulfonation is dried into powder by hot air at 240-260°C. 4. according to the method for making sodium lignosulfonate described in any one of claims 1 to 3, it is characterized in that: described sulfonating agent is sodium hydroxysulfate or sodium sulfite, and add-on is wt 2-30%. 5. according to the method for making sodium lignosulfonate described in any one of claims 1 to 3, it is characterized in that: described catalyzer is ferrous sulfate, manganese dioxide or ferric chloride, and add-on is wt 1 -5%. 6. according to the method for making sodium lignosulfonate described in any one of claim 1 to 3, it is characterized in that: described oxygenant is that concentration is 30-50% hydrogen peroxide, and add-on is wt 1-10%. 7. according to the method for manufacturing sodium lignosulfonate described in any one of claims 1 to 3, it is characterized in that: described lignin is liquid acid analysis lignin, hot flue gas, sulfuric acid dioxide analysis lignin or through drying processed lignin. 8. the method for manufacturing sodium lignosulfonate according to claim 1, is characterized in that: the solution concentration solid content after described dissolving is wt38%.

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